Do good things happen to people who think nice thoughts? Do nasty people eventually get punished in the end?

It sounds good in theory, but how do you explain all the rich jerks in the world?

The concept of karma has taken root in our culture. It's come from ancient Indian religions to become a 21st century pop culture term.

I believe that one of the reasons we're still talking about it is because we see increasing evidence of its truth.

It doesn't always work fast, and it doesn't always work perfectly, but I think it's real.

Here's why:

People can read your vibe.

Social science reveals that as much as 93 percent of our response to other people is to the unspoken messages they give off. A mere 7 percent of our response is to the actual words they say. The rest of our response -- consciously and unconsciously -- is to their "vibe," their inner script and emotions being revealed by their facial expression, tone and body language.

If a person walks into a room angry, excited or sad, you mentally prepare yourself to deal with them, before they've even said a word. You're either bracing your gut for their anger, wondering what they're excited about or reaching out your arms to console them in their pain.

Daily examples may be more subtle, but whether we realize it or not, people are always responding to the unspoken messages we give off.

That's where karma kicks in.

Your inner thoughts and words create your reality. They set the tone for your interactions, and your interactions set the tone for your life.

For example: Can you tell the difference between a teacher, trainer or boss who is delighted to help you learn versus one who thinks you're an intrusive pain in their backside?

Of course you can, and it affects the way you interact with them.

Here's where it gets even more exciting (or scary depending on perspective).

The brain is like any other muscle. The parts you use get stronger, and the parts you don't use begin to atrophy.

If you make enthusiasm, happiness and grace a habit, those neural pathways strengthen and over time they become easier to access and use.

If anger, criticism and judgment are a daily mental habit, those pathways get stronger. And if you shut down the neural pathways for compassion, goodwill and humor long enough, you get to the point where you can't access them even if you want to.

So while it might seem like you're in a bad mood because you work with a bunch of jerks, over time you become the person you've been acting like.

And the world responds accordingly.

It doesn't matter whether or not you believe in the spiritual aspects of karma. The social science is clear. If you continually think bad thoughts you literally change the chemistry of your own brain, which changes the way people respond to you.

Karma, it's the cycle of cause and effect. It's real, and it's powerful.

Lisa Earle McLeod is the author of three books, including "The Triangle of Truth: The Surprisingly Simple Secret to Resolving Conflicts Large and Small," a Washington Post Top 5 Book for Leaders.